Short version: can Night's Watch Jon Snow be removed from a challenge with Highgarden?

Jon Snow is "considered to be participating in a challenge if he is standing" any time a Night's Watch character is attacking. Highgarden says stand a participating character and remove them from the challenge. Now I know it doesn't matter that he's already standing because it says "and" not "then" but does Jon's text override the one time effect of Highgarden? Would he just immediately be considered particiating again because he's standing or would the removal permanently remove him?

He would immediately be considered to be participating again because his ability is a continuous effect.

So actually, since Jon is already standing and he would immediately be participating again, you would not be allowed to trigger Highgarden on Jon in the first place because the game state will not change.

You can only remove him indirectly by removing the other Night's Watch character attacking (if there is only 1, of course).

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